In recent years, liquid crystal display devices, for example, are widely used in liquid crystal televisions, monitors, mobile phones, and the like as a flat panel display having advantages compared to conventional cathode-ray tubes in being thinner, lighter, and the like. Among such liquid crystal display devices, those that use an active matrix substrate having a plurality of data lines (source lines) and a plurality of scan lines (gate lines) arranged in a matrix, and having arranged in a matrix switching elements such as thin film transistors (TFTs) in the vicinity of the intersection between the data lines and scan lines, and pixels having pixel electrodes connected to these switching elements in a liquid crystal panel as a display panel are known.
As disclosed in Patent Document 1 below, for example, a configuration is proposed for such conventional active matrix substrates in which three short bars are provided such that separate test signals are inputted respectively to data lines corresponding to red (R), green (G), and blue (B) pixels. In other words, in this conventional active matrix substrate, a plurality of data lines corresponding to the R pixels are connected to a first short bar. A plurality of data lines corresponding to G pixels are connected to a second short bar, and a plurality of data lines corresponding to B pixels are connected to a third short bar. As a result, in the conventional active matrix substrate, by inputting separate test signals to each of the first to third short bars, it was possible to input different test signals to each of the data lines for each of the colors RGB.